Electric flash lamp



M. GOODFELLOW.

ELECTRIC FLASH LAMP.

APPLICAUON FILED AuG.12. 192|.

Patented Jan. 24, 1922.

UNITED STATES( HAGNUS GOODFELLOW, 0F LONDON, ENGLAND, ASSIGNOB T0 THE EVER READY COM- Awxrlsrrr oFFlcE.

PANY (GREAT BRITAIN) LIMITED, OF LONDON, ENGLAND, A BRITISH COMPANY.

ELECTRIC FLASH' LAMP'.

Patented Jan. 24, 1922.

Application led August 12, 1921. Serial No. 491,680.

(GRANTEDUNDEB THE PROVISIONS 0F THE ACT 0F KARCH 3, 1921, 41 STAT. L., 1313.)

T o all whom it. may concern.'

Be it known that' I, MAGNUS GooDFELLow, a subject of the King of England, residing at London, England, have invented certaln new and useful Improvements in Electric Flash Lamps, (for which I have filed a -lication in Great Britain Nov. 30, 1917, atent No. 115,381 of 1918,) of which the following is a specification. a

This invention is for an electric selfcontained fiash lamp of the type wherein there are employed inner and outer casings whereon the one casing slides relatively to the other and switch mechanism interconnects the two casings so that when the one casing is slid into one position the circuit is closed and when it is slid into the other position it is open.

According to this invention a flash lamp of the type described is characterized by the outer casing being sleeve-like and open at both ends and the inner casing or tray made to carry the bulb as well as the battery in such manner that the bulb is covered by the outer casing in the open circuit position and theinner casing is made to protrude from one end of the outer casing to expose the bulb and close the circuit.

' Preferably the lamp is made in the form of a match-box of the type having a sliding interior, which interior in this case carries the bulb and battery, and when pushed partially out exposes the bulb and completes the circuit so that the filament is energized. l

In the accompanying drawings- Y Figure 1 is a perspective view of a fiash lamp according to one method of carrying out this invention;

Figure 2 is a face view of the lamp in longitudinal section showing the switch mechanism; and v Figure 3 is a view similar to Figure 2 but with the parts in a different position.

The same letters indicate the same parts throughout the drawin s.

The casing for the amp is made to resemble in form a match-box having an outer casing A open at both ends and an interior sliding casing or tray A1. In the tray and near one end of the same a bulb socket B is secured having its central terminal B1 connected by a wire B2 to a brass strip C secured on the outer face of one of the sides of the tray A1. A plate D is secured at the bottom of the tray near the side to which the stri C is fastened and this late has a lug 1 which extends o utwar ly along the inner face of the said side and on the lug 1s a projection D2 vhich lies in an opening A2 formed in the side of the tray.

The plate D has a tongue D3 which bears against the terminal E1 ofthe battery E. The battery lies in the tray A1 between the end of the tray and the bulb socket B so that one .of its terminals can bear against the projection D3 as already described and the other terminal E2 can bear against the side of. the bulb socket B. The bulb B3 screws 1nto the socket in the usual manner thus making one contact for the filament of the 'bulb through the'outer shell, carryingthe bulb, and the socket,l B, the other contact for the filament being through the usual central stud which is insulated from the outer shell and bears against the part B1, whlch is also insulated from the socket.

A resilient tongue F is secured by one end to the inner face of one of the sides of the outer casing A being fastened thereto by a rivet as shown at F1. This tongue lies opposite the strip C and has at its end a tapered contact plece F2. The strip C has in it a perforation C1 which lies opposite the orifice A2 in the side of the tray. The strip also has another perforation ,C2 which 1s lnear one end of the tray and the side of the tray is recessed or this orifice C2.

The operation of this lamp is as follows When the tray is in the closed position, as shown in Figure 2, that is in the same position as the interior of a match box would be when the box is closed, the end perforated opposite F2 of the tongue F is held by the resiliency of the tongue in the orifice .C2 of the strip C. In this position the tongue serves as a locking device to prevent the tray from sliding out, and the circuit is open because no connection exists between the strip C and the plate D. If the tray A1, however, is pushed out with the bulb end foremost, as shown in Figure l, the projecting end F2 of the tongue F is made to ride out of the orifice C2 and finally drops into the orifice C1. This end F2 is shaped to make contact with the sides of the orifice C1 and also prowith the pro'ection D2 on the lug D1l of the plate D. T is completes the circuit with the bulb so that the bulb, which is now exposed `beyond the outer casing A, will become luminous. The projection-F2 engaging the orifice C1 in addition to closing the circuit acts again as a detent to prevent accidental displacement of the tray A1, but' it does not prevent the tray from being forcibly pushed-vin sov that the parts can again be brought to the position shown in Figure 2. I

It will be observed Athat the strip C is slightly bowed in Figure 2, so that it stands away from the outer side of the'tra wheref as in Figure 3 it lies flat against t e same. The object of this is -to jensure that the tapered projection F2 shall make contact'wlth both the strip and. the stud D2. It wlll be seen that if the tapered projectlon is made of such dimensions that 1t will fill the orifice C1, and then push the strip C flat against the tray A1 so that its end comes into contact with the stud D, metallic contact with both these parts is ensured. It is not essential to have the strip C bowed as the tray is almost sure to be pushed to such a position that one side or other of the orifice C1 will make contact with the projection F2, and then all that is necessary is that the projection shall be long enough to ensure contact with the stud D.

The resilience of the tongue F whilst operating to cause the end F2 to engage the orifice C1 or C2 is not necessarily dependent only upon this Afoi` its engagement as the side of the.y casing A has some degree gut the bulb in this case was carried of resilience and can also be utilized to urge the end F2 into either of the said orifices.

It will be appreciated that a lam according to this invention may be ma e up in varlous shapes and the case may be iinished in leather or other material as required and decorated according to taste.

It has before been proposed to employ a casing carrying the battery which could slide in one end of an outer casing (which casing' was closed at the other end) for the urpose of closing or opening the circut, y the outer casing and always exposed to view; it has also been proposed to provide a walking stick carrying a battery and bulb at its top end with a cover ca which cap 'when slid u wards exposed lt e bulb between it` an the stick and completedthe circuit; no claim is made in the present specification for such devices.

What I claim as m invention and desire to secure b Letters atent is 1. In a ash-lamp the combination of an outer sleeve-like casing open at both ends, a tray slidablelongitudinally within the said outer casing, meansl to support an electric `lamp-bulb within the tray in such a `ciently to expose the lamp-bulb and means to connect a battery withln the tray to the lam -bulb throu h the said switch, substantial y as Set forti.

2. In a flashlamp, the combination with an outer sleeve-like casin and a tray slid.

able longitudinally therein having substantially the proportions of a match-box with its' tray, of means to support an electric lamp-bulb within the tray in such a position that it is exposed to view by a sliding movement of the tray within the said casing less than suiiicient to 'withdraw the tray completely from the casing, an automatic switch whereof one part is mounted upon the tray and a co-operating part upon the lcasing 1n sucha manner that the clrcuit is open when the tra is housed within the casing, but is close when the tray is made to rotrude suliiciently to expose the lampbul, one of saidl switch parts constituting a detent and adapted to enga e with that one of the two re atively slida le members upon which it is not mounted and to arrest the same against slidin movement when the circuit is closed, an means to connect the battery within the tray to the lamp-bulb throuh the said switch, substantially as dcscribe l 3. In a flash-lamp the combination of an outer sleeve-like casingopen at both ends, a tray slidable longitudinally within the said outer casing, means to support an electric lamp-bulb within the tray 1n such a position that it is exposed to view by a sliding movement of the tray within the said casing less tihar slflicien1 to withdraw thlJ1 tray com ete rom t e casin a 'e in y contiiolledydetent secured togone oilthe sid two parts which have relative sliding movement, a metal strip secured to the other of the said two parts in such a position as to afford `a sliding track for the free end of the detent and provided with an aperture so situated as to' receive the detent when the tray is protruded to expose the lamp, a contact-piece supported in such a position opposite the said aperture that the detent when entering the latter makes contact both with the apertured strip and the said contact-piece, and means to connect a battery within the tray in series with the lamp-bulb to the said contact-piece and lmetal strip, substantially as set forth.

i 4.15 a sash-lamp the combination of au outer sleeve-like casing open at both ends, a

. tray slidable longitudinally within the said l than suflicient to withdraw the tray com? pletely from the casing, a resilient tongue secured to one of the said two parts which have relative sliding -movement provided with a projection near its free end extending towards the other of the said two parts, a metal strip secured to the said other 'part in such a osition as to afford a sliding track for the said projection upon the tongue and so situated as to receive the projection when the tray is protr'uded to expose the lamp, a contact-piece supported on the said other part in such a position opposite the said aperture that the projection when entering the latter makes contact both with the apertured strip and the said contact-piece, and means to connect a battery within the tray in series with the lamp-bulb to the said contact-piece and metal-strip, substantially as set forth.

5. In a flash-lamp the combination of an outer sleeve-like casin open at both ends, a tray slidable longitudinally within the said outer casing, means to support an electric lamp-bulb within the tray in such a position that it is exposed to view by a sliding movement of the tray within the said casing less than sufiicient to withdraw the tray coinpletely from the casing, an automatic switch whereof some parts are mounted upon the tray and co-operating parts upon the interior of the casing in such a manner that the circuit is o en when the tray is housed within the casing but is closed when the tray is made to rotrude sufiiciently to expose the lamp-bu b, a metallic plate within the tray so situated as to press upon one contact-strip of an ordinary dry battery when placed within the trayv and also to afford a switch-contact for co-operation with the co-operating parts mounted upon the interior of the casing, substantially as set forth. A

A 6. In a Hash-lamp the combination of an outer sleeve-like casing open at both ends, a tray slidable longitudinally within the said outer casing, means to support an electric lamp-bulb within the tray in such a position that it is exposed to view by a sliding movement of the tray within the said casing less than sufiicient to withdraw the tray completely from the casing, a resilient tongue secured to one of the said two parts which have relative sliding movement provided with a projection near its free end extending towards the other of the said two parts, a metal strip secured to the said other part in such a position as to afford a sliding track for the said projection union the tongue and so situated as to receive t e projection when the tray is protruded to. expose the lamp, a metal plate secured to the interior of the tray havin a projection extending away from a wa 1 of the tray in such a position as to press upon one connectin strip of an ordinary dry battery when p aced within.

the tray and havin a second projection so situated opposite' t e said aperture in the metal strip as to receive and makecontact with the projection upon the tongue when the said projection enters the latter in such a manner as to make contact also with thc strip, substantially as set forth. i

7. In a fiash-lamp the combination of aov outer sleeve-like casing and a tray slidable therein having substantially the proportions of a match-box with its tray, means to support an electric lamp-bulb within the tray in such a position that it is exposed to view by a sliding movement of the tray within the said casing less than sufiicient to withdraw the tray completelyv from the casin, a resilient tongue mounted upon the interior of the casing and having a metallic projection extending towards the tray, a metallic strip secured .to the exterior of a wall of the tray in such a position as to be presented to the said rojection on the tongue and provide a sliding track therefor and having an aperture to receive the said projection when the tray is protruded to expose the lamp, a contact-piece supported in thetray adapted to Apress upon one connecting strip of an ordinary dry battery when placed within the tray so situated opposite to the said aperture as to receive the projection upon the tongue when the latter enters the said aperture and also makes Contact with the said metal strip and a connectin conductor extending from one termina of the lamp-support to the said metal strip, substantially as set forth.

8. In a flash-lamp the combination of an outer sleeve-like casing and a tray slidable therein having substantially the proportions.

of a match-box with its4 tray, means to support an electric lamp-bulb within the tray in such a position that it is exposed to View by a sliding movement of. the tray within the said casing less than sufficient to withdraw the tray completely from the casing, a resilient tongue mounted upon the interior of the casing and having a metallic projection extending towards the tray, a metallic strip secured to the exterior of a wall of the tray in such a position as to be presented to the said projection on the tongue and provide a sliding track therefor and having one aperture to receive the said projection when the tray is rotruded to expose the lam and a secon aperture to receive the sai projection when the tray is enclosed within the casing, a contacta sliding piece supported in the tray adapted to 'press' upon one connecting strip. of an ordinary dry battery when placed withln the tray so situated opposite the first said aplerture as to receive the projection upon t e tongue when the latter enters the sald aperture .and also makes contact with the said metal strip and a connecting conductor extendin from one terminal of the lam -supportvto t e said metal strip, substantial y as set forth.

' 9. In a fiashlamp, the combination with an outer sleeve-like member, an inner member constituting a tray slidablelongltudinally therein and means to support an electric lamp-bulb within the tra in such a. position that it will be expose to vlew by movement of the inner member in relation to the outer member less than sufiicient to withdraw the tray completely from the outer member, of an automatic `part mounted u pon the interior of the said switch comprising one part that is mounted upon said inner member and a cooperating outer member 1n such a manner that the switch is open when the tray is housed within the outer member, but is closed when the tray is made to-protrude sufliciently to expose, the lamp-bulb, said inner member .having two spaced perforations in oneiof its walls and said second part of the switch constituting a detent ada ted to enter said holes' in two positions o said inner member, one of said positions corresponding `to that in which the switch is closed, and means for connecting a batter within said inner member to the lamp-bu b through the said switch, substantially as described.

In testimony whereof I` aflix my signatur-e.

MAeNUsI GooDFELLoW. 

